Communities
Two families, one reason.
A standard community is two 16-bit halves. AS202192 is a 32-bit number and simply does not fit in the first half, and neither do the ASNs of most networks assigned one in the last decade. Anything that has to name us, or name a peer with a 32-bit ASN, is therefore an RFC 8092 large community. The two controls that do not need our ASN, and two well-known communities, work in the standard form as well, so a router that cannot set large communities is not shut out of the cases that matter.
Standard
For routers without large communities
| Community | Effect |
|---|---|
| 0:0 | Do not announce to anyone |
| 0:<peer-asn> | Do not announce to <peer-asn>. Works only for peers whose ASN fits in 16 bits |
| 65535:666 | Blackhole a /128, RFC 7999. The same treatment as the large form below |
| 65535:0 | GRACEFUL_SHUTDOWN, RFC 8326. Your routes are de-preferred before you take the session down |
Selective announcement to a 32-bit peer, and prepending, cannot be expressed this way by anyone. If you need those, use the large form below or ask us to set a white list on your session.
Large
Steer your announcements
| Community | Effect |
|---|---|
| 202192:0:0 | Do not announce to anyone |
| 202192:0:<peer-asn> | Do not announce to <peer-asn> |
| 202192:1:<peer-asn> | Announce to <peer-asn>, used together with 202192:0:0 |
| 202192:101:0 | Prepend your ASN once towards everyone |
| 202192:102:0 | Prepend your ASN twice towards everyone |
| 202192:103:0 | Prepend your ASN three times towards everyone |
| 202192:101:<peer-asn> | Prepend once towards <peer-asn> |
| 202192:102:<peer-asn> | Prepend twice towards <peer-asn> |
| 202192:103:<peer-asn> | Prepend three times towards <peer-asn> |
| 202192:65281:0 | Add NO_EXPORT when announcing to everyone |
| 202192:65534:0 | Blackhole a /128 out of a prefix you already announce. The next hop is rewritten to 2a0b:4e07:42::ffff and NO_EXPORT is added |
Announcing to everyone is the default and needs no tag. A route carrying 202192:0:0 goes to nobody except the peers named with 202192:1:<peer>. Without it, a route goes to everybody except the peers named with 202192:0:<peer>. Prepends are applied after the decision to announce, and the standard and large forms may be mixed on the same route.
Informational
Attached by the servers
| Community | Meaning |
|---|---|
| 202192:1000:1 | RPKI valid |
| 202192:1000:2 | RPKI not-found, accepted on IRR data |
| 202192:1000:3 | Origin ASN present in the AS-SET |
| 202192:1000:4 | Origin ASN not present in the AS-SET |
| 202192:1000:5 | Prefix present in the AS-SET |
| 202192:1000:6 | Prefix not present in the AS-SET |
| 202192:1000:7 | RPKI invalid, route rejected |
| 202192:1000:8 | Prefix accepted on a covering ROA rather than IRR data |
| 202192:1000:9 | Route accepted through an operator white list |
| 202192:1100:<n> | Rejected, cause <n> from the table below |
These are stripped from a route before it is announced to another member. You see them on your own session and on the looking glass.
Reject causes
Why a route is missing.
| 202192:1100:n | Cause |
|---|---|
| 1 | AS_PATH longer than 32 |
| 2 | Prefix is a bogon |
| 3 | Prefix is on the global blacklist: our own block, other IXP peering LANs |
| 4 | Wrong address family |
| 5 | NEXT_HOP is not the peer's own address |
| 6 | Left-most ASN is not the peer's ASN |
| 7 | Private or reserved ASN in AS_PATH |
| 8 | Transit-free ASN in AS_PATH |
| 9 | Origin ASN not in the peer's AS-SET |
| 10 | Prefix outside IPv6 global unicast |
| 11 | Prefix on the peer's own blacklist |
| 12 | Prefix not in the peer's AS-SET and not covered by a ROA |
| 13 | Prefix length outside /16 to /48 |
| 14 | RPKI invalid |
| 15 | An ASN that asked never to be reached via route servers is in AS_PATH |
Checks run in the order given on the route servers page, so a route that fails the IRR check is tagged 12 even when it is RPKI-invalid as well. A rejected route is never re-announced; it is kept only so the looking glass can explain it.